OpenOffice.org maintains index pages for case studies and deployments.

In 2005, Banco do Brasil began a process of migration to the open source software suite OpenOffice.org. The migration commenced with the installation of the package “OpenOffice.org 2.0”. As of February 2007, this suite is found installed in more than 71,000 workstations, distributed among the branches and corporate offices.

Oxford Archaeology, one of Europe's largest independent archaeology practices, are commited to their ground-breaking Open Archaeology programme. This has several strands - to quote their website at http://thehumanjourney.net/

"...a philosophy, some software, a commitment to adopting and developing standards, making archaeological knowledge free to access, a passion. Open Archaeology is all of these."

The city of Haarlem – capital of North Holland – has migrated 2000 desktops to OpenOffice (which supports the OpenDocument format). Jan van de Straat, Director of R&D for the city, found that OpenOffice did not lack any functionality that was used and needed by the city’s employees.

A description of Vienna's OpenOffice.org migration was presented at OpenOffice.org Conference.
See also the project website (in German).